Buildout is the recommended way to install Plumi. It is developed and maintained at https://github.com/plumi/plumi.app/
Check out the instructions at https://github.com/plumi/plumi.app/blob/master/docs/INSTALL.rst to have a running Plumi site within an hour!
Latest version tag is 4.5.1.
A final stable release of the Plumi 4.5 buildout package is also available at http://pypi.python.org/pypi/plumi.app/
Installing & Developing Plone
Plumi is based on Plone. The Plone developers manual covers installation, development and troubleshooting of Plone sites.